RE: A assert failure when initdb with track_commit_timestamp=on

Dear Fujii-san, Andy,

> Shouldn't we also add a TAP test to verify that initdb works correctly
> with GUCs marked as GUC_NOT_IN_BOOTSTRAP?

Another place we can put the test is 001_initdb.pl, like:

```
--- a/src/bin/initdb/t/001_initdb.pl
+++ b/src/bin/initdb/t/001_initdb.pl
@@ -331,4 +331,15 @@ command_fails(
[ 'pg_checksums', '--pgdata' => $datadir_nochecksums ],
"pg_checksums fails with data checksum disabled");

+# Some GUCs like track_commit_timestamp cannot be set to non-default value in
+# bootstrap mode becasue they may cause crash. Ensure settings can be surely
+# ignored.
+command_ok(
+ [
+ 'initdb', "$tempdir/dataXX",
+ '-c' => 'track_commit_timestamp=on',
+ '-c' => 'transaction_timeout=200s'
+ ],
+ 'successful creation with ignored settings');
+
```

But both Andy's patch and mine assume that post-bootstrap transactions can be
finished within the specified time. Extremely long value is set above but I
cannot say all machine won't spend 200s here...

Best regards,
Hayato Kuroda
FUJITSU LIMITED